$(function()
{
  $.getJSON(
    '/track/ajax/itineraries/',
    function(data)
    {
      $.each(
        data,
        function(id)
        {
          $.each(
            this.checkpoints,
            function(id)
            {
              console.log(id);
              console.log(this);
            });
          
          console.log(this.checkpoints[0]);
        });
    });
});
